Files
cloudron-box/src/cert/acme.js
Girish Ramakrishnan be4d2afff3 fix path to cert
2015-12-12 20:30:50 -08:00

370 lines
15 KiB
JavaScript

/* jslint node:true */
'use strict';
var assert = require('assert'),
async = require('async'),
config = require('../config.js'),
crypto = require('crypto'),
debug = require('debug')('box:cert/acme'),
fs = require('fs'),
path = require('path'),
paths = require('../paths.js'),
safe = require('safetydance'),
superagent = require('superagent'),
ursa = require('ursa'),
util = require('util'),
_ = require('underscore');
var CA_PROD = 'https://acme-v01.api.letsencrypt.org',
CA_STAGING = 'https://acme-staging.api.letsencrypt.org/',
LE_AGREEMENT = 'https://letsencrypt.org/documents/LE-SA-v1.0.1-July-27-2015.pdf';
exports = module.exports = {
getCertificate: getCertificate
};
function AcmeError(reason, errorOrMessage) {
assert.strictEqual(typeof reason, 'string');
assert(errorOrMessage instanceof Error || typeof errorOrMessage === 'string' || typeof errorOrMessage === 'undefined');
Error.call(this);
Error.captureStackTrace(this, this.constructor);
this.name = this.constructor.name;
this.reason = reason;
if (typeof errorOrMessage === 'undefined') {
this.message = reason;
} else if (typeof errorOrMessage === 'string') {
this.message = errorOrMessage;
} else {
this.message = 'Internal error';
this.nestedError = errorOrMessage;
}
}
util.inherits(AcmeError, Error);
AcmeError.INTERNAL_ERROR = 'Internal Error';
AcmeError.EXTERNAL_ERROR = 'External Error';
AcmeError.ALREADY_EXISTS = 'Already Exists';
AcmeError.NOT_COMPLETED = 'Not Completed';
AcmeError.FORBIDDEN = 'Forbidden';
// http://jose.readthedocs.org/en/latest/
// https://www.ietf.org/proceedings/92/slides/slides-92-acme-1.pdf
// https://community.letsencrypt.org/t/list-of-client-implementations/2103
function getNonce(callback) {
superagent.get(CA_STAGING + '/directory', function (error, response) {
if (error) return callback(error);
if (response.statusCode !== 200) return callback(new Error('Invalid response code when fetching nonce : ' + response.statusCode));
return callback(null, response.headers['Replay-Nonce'.toLowerCase()]);
});
}
// urlsafe base64 encoding (jose)
function urlBase64Encode(string) {
return string.replace(/\+/g, '-').replace(/\//g, '_').replace(/=/g, '');
}
function b64(str) {
var buf = util.isBuffer(str) ? str : new Buffer(str);
return urlBase64Encode(buf.toString('base64'));
}
function sendSignedRequest(url, accountKeyPem, payload, callback) {
assert.strictEqual(typeof url, 'string');
assert(util.isBuffer(accountKeyPem));
assert.strictEqual(typeof payload, 'string');
assert.strictEqual(typeof callback, 'function');
var privateKey = ursa.createPrivateKey(accountKeyPem);
var header = {
alg: 'RS256',
jwk: {
e: b64(privateKey.getExponent()),
kty: 'RSA',
n: b64(privateKey.getModulus())
}
};
var payload64 = b64(payload);
getNonce(function (error, nonce) {
if (error) return callback(error);
debug('Using nonce %s', nonce);
var protected64 = b64(JSON.stringify(_.extend({ }, header, { nonce: nonce })));
var signer = ursa.createSigner('sha256');
signer.update(protected64 + '.' + payload64, 'utf8');
var signature64 = urlBase64Encode(signer.sign(privateKey, 'base64'));
var data = {
header: header,
protected: protected64,
payload: payload64,
signature: signature64
};
superagent.post(url).set('Content-Type', 'application/x-www-form-urlencoded').send(JSON.stringify(data)).end(function (error, res) {
if (error && !error.response) return callback(error); // network errors
callback(null, res);
});
});
}
function registerUser(accountKeyPem, email, callback) {
assert(util.isBuffer(accountKeyPem));
assert.strictEqual(typeof email, 'string');
assert.strictEqual(typeof callback, 'function');
var payload = {
resource: 'new-reg',
contact: [ 'mailto:' + email ],
agreement: LE_AGREEMENT
};
debug('registerUser: %s', email);
sendSignedRequest(CA_STAGING + '/acme/new-reg', accountKeyPem, JSON.stringify(payload), function (error, result) {
if (error) return callback(new AcmeError(AcmeError.EXTERNAL_ERROR, 'Network error when registering user: ' + error.message));
if (result.statusCode === 409) return callback(new AcmeError(AcmeError.ALREADY_EXISTS, result.body.detail));
if (result.statusCode !== 201) return callback(new AcmeError(AcmeError.EXTERNAL_ERROR, util.format('Failed to register user. Expecting 201, got %s %s', result.statusCode, result.text)));
debug('registerUser: registered user %s', email);
callback();
});
}
function registerDomain(accountKeyPem, domain, callback) {
assert(util.isBuffer(accountKeyPem));
assert.strictEqual(typeof domain, 'string');
assert.strictEqual(typeof callback, 'function');
var payload = {
resource: 'new-authz',
identifier: {
type: 'dns',
value: domain
}
};
debug('registerDomain: %s', domain);
sendSignedRequest(CA_STAGING + '/acme/new-authz', accountKeyPem, JSON.stringify(payload), function (error, result) {
if (error) return callback(new AcmeError(AcmeError.EXTERNAL_ERROR, 'Network error when registering domain: ' + error.message));
if (result.statusCode === 403) return callback(new AcmeError(AcmeError.FORBIDDEN, result.body.detail));
if (result.statusCode !== 201) return callback(new AcmeError(AcmeError.EXTERNAL_ERROR, util.format('Failed to register user. Expecting 201, got %s %s', result.statusCode, result.text)));
debug('registerDomain: registered %s', domain);
callback(null, result.body);
});
}
function prepareHttpChallenge(accountKeyPem, challenge, callback) {
assert(util.isBuffer(accountKeyPem));
assert.strictEqual(typeof challenge, 'object');
assert.strictEqual(typeof callback, 'function');
debug('prepareHttpChallenge: preparing for challenge %j', challenge);
var token = challenge.token;
var privateKey = ursa.createPrivateKey(accountKeyPem);
var jwk = {
e: b64(privateKey.getExponent()),
kty: 'RSA',
n: b64(privateKey.getModulus())
};
var shasum = crypto.createHash('sha256');
shasum.update(JSON.stringify(jwk));
var thumbprint = urlBase64Encode(shasum.digest('base64'));
var keyAuthorization = token + '.' + thumbprint;
debug('prepareHttpChallenge: writing %s to %s', keyAuthorization, path.join(paths.ACME_CHALLENGES_DIR, token));
fs.writeFile(path.join(paths.ACME_CHALLENGES_DIR, token), token + '.' + thumbprint, function (error) {
if (error) return callback(new AcmeError(AcmeError.INTERNAL_ERROR, error));
callback();
});
}
function notifyChallengeReady(accountKeyPem, challenge, callback) {
assert(util.isBuffer(accountKeyPem));
assert.strictEqual(typeof challenge, 'object');
assert.strictEqual(typeof callback, 'function');
debug('notifyChallengeReady: %s was met', challenge.uri);
var keyAuthorization = fs.readFileSync(path.join(paths.ACME_CHALLENGES_DIR, challenge.token), 'utf8');
var payload = {
resource: 'challenge',
keyAuthorization: keyAuthorization
};
sendSignedRequest(challenge.uri, accountKeyPem, JSON.stringify(payload), function (error, result) {
if (error) return callback(new AcmeError(AcmeError.EXTERNAL_ERROR, 'Network error when notifying challenge: ' + error.message));
if (result.statusCode !== 202) return callback(new AcmeError(AcmeError.EXTERNAL_ERROR, util.format('Failed to notify challenge. Expecting 202, got %s %s', result.statusCode, result.text)));
callback();
});
}
function waitForChallenge(challenge, callback) {
assert.strictEqual(typeof challenge, 'object');
assert.strictEqual(typeof callback, 'function');
debug('waitingForChallenge: %j', challenge);
async.retry({ times: 10, interval: 5000 }, function (retryCallback) {
debug('waitingForChallenge: getting status');
superagent.get(challenge.uri).end(function (error, result) {
if (error && !error.response) {
debug('waitForChallenge: network error getting uri %s', challenge.uri);
return retryCallback(new AcmeError(AcmeError.EXTERNAL_ERROR, error.message)); // network error
}
if (result.statusCode !== 202) {
debug('waitForChallenge: invalid response code getting uri %s', result.statusCode);
return retryCallback(new AcmeError(AcmeError.EXTERNAL_ERROR, 'Bad response code:' + result.statusCode));
}
debug('waitForChallenge: status is "%s"', result.body.status);
if (result.body.status === 'pending') return retryCallback(new AcmeError(AcmeError.NOT_COMPLETED));
else if (result.body.status === 'valid') return retryCallback();
else return retryCallback(new AcmeError(AcmeError.EXTERNAL_ERROR, 'Unexpected status: ' + result.body.status));
});
}, callback);
}
// https://community.letsencrypt.org/t/public-beta-rate-limits/4772 for rate limits
function signCertificate(accountKeyPem, csrDer, callback) {
assert(util.isBuffer(accountKeyPem));
assert(util.isBuffer(csrDer));
assert.strictEqual(typeof callback, 'function');
var payload = {
resource: 'new-cert',
csr: b64(csrDer)
};
debug('signCertificate: signing %s', payload.csr);
sendSignedRequest(CA_STAGING + '/acme/new-cert', accountKeyPem, JSON.stringify(payload), function (error, result) {
if (error) return callback(new AcmeError(AcmeError.EXTERNAL_ERROR, 'Network error when signing certificate: ' + error.message));
if (result.statusCode !== 201) return callback(new AcmeError(AcmeError.EXTERNAL_ERROR, util.format('Failed to sign certificate. Expecting 201, got %s %s', result.statusCode, result.text)));
if (!('location' in result.headers)) return callback(new AcmeError(AcmeError.EXTERNAL_ERROR, 'Missing location in downloadCertificate'));
var certificateLocation = result.headers.location;
debug('signCertificate: certificate is available at %s', certificateLocation);
superagent.get(certificateLocation).buffer().parse(function (res, done) {
var data = [ ];
res.on('data', function(chunk) { data.push(chunk); });
res.on('end', function () { res.text = Buffer.concat(data); done(); });
}).end(function (error, result) {
if (error && !error.response) return callback(new AcmeError(AcmeError.EXTERNAL_ERROR, 'Network error when downloading certificate'));
if (result.statusCode === 202) return callback(new AcmeError(AcmeError.INTERNAL_ERROR, 'Retry not implemented yet'));
if (result.statusCode !== 200) return callback(new AcmeError(AcmeError.EXTERNAL_ERROR, util.format('Failed to get cert. Expecting 200, got %s %s', result.statusCode, result.text)));
callback(null, result.text);
});
});
}
function downloadCertificate(accountKeyPem, domain, outdir, callback) {
assert(util.isBuffer(accountKeyPem));
assert.strictEqual(typeof domain, 'string');
assert.strictEqual(typeof outdir, 'string');
assert.strictEqual(typeof callback, 'function');
var execSync = safe.child_process.execSync;
var privateKeyFile = path.join(outdir, domain + '.key');
var key = execSync('openssl genrsa 4096');
if (!key) return callback(new AcmeError(AcmeError.INTERNAL_ERROR, safe.error));
if (!safe.fs.writeFileSync(privateKeyFile, key)) return callback(new AcmeError(AcmeError.INTERNAL_ERROR, safe.error));
debug('downloadCertificate: key file saved at %s', privateKeyFile);
var csrDer = execSync(util.format('openssl req -new -key %s -outform DER -subj /CN=%s', privateKeyFile, domain));
if (!csrDer) return callback(new AcmeError(AcmeError.INTERNAL_ERROR, safe.error));
signCertificate(accountKeyPem, csrDer, function (error, certificateDer) {
if (error) return callback(error);
safe.fs.writeFileSync(path.join(outdir, domain + '.der'), certificateDer);
debug('downloadCertificate: cert der file saved');
var certificatePem = execSync('openssl x509 -inform DER -outform PEM', { input: certificateDer }); // this is really just base64 encoding with header
if (!certificatePem) return callback(new AcmeError(AcmeError.INTERNAL_ERROR, safe.error));
var chainPem = safe.fs.readFileSync(__dirname + '/lets-encrypt-x1-cross-signed.pem.txt');
if (!chainPem) return callback(new AcmeError(AcmeError.INTERNAL_ERROR, safe.error));
var certificateFile = path.join(outdir, domain + '.cert');
var fullChainPem = Buffer.concat([certificatePem, chainPem]);
if (!safe.fs.writeFileSync(certificateFile, fullChainPem)) return callback(new AcmeError(AcmeError.INTERNAL_ERROR, safe.error));
callback();
});
}
function acmeFlow(domain, email, accountKeyPem, outdir, callback) {
assert.strictEqual(typeof domain, 'string');
assert.strictEqual(typeof email, 'string');
assert(util.isBuffer(accountKeyPem));
assert.strictEqual(typeof outdir, 'string');
assert.strictEqual(typeof callback, 'function');
registerUser(accountKeyPem, email, function (error) {
if (error && error.reason !== AcmeError.ALREADY_EXISTS) return callback(error);
registerDomain(accountKeyPem, domain, function (error, result) {
if (error) return callback(error);
debug('acmeFlow: challenges: %j', result);
var httpChallenges = result.challenges.filter(function(x) { return x.type === 'http-01'; });
if (httpChallenges.length === 0) return callback(new AcmeError(AcmeError.EXTERNAL_ERROR, 'no http challenges'));
var challenge = httpChallenges[0];
async.series([
prepareHttpChallenge.bind(null, accountKeyPem, challenge),
notifyChallengeReady.bind(null, accountKeyPem, challenge),
waitForChallenge.bind(null, challenge),
downloadCertificate.bind(null, accountKeyPem, domain, outdir)
], callback);
});
});
}
function getCertificate(domain, outdir, callback) {
var email = 'admin@' + config.fqdn();
var accountKeyPem;
if (!fs.existsSync(paths.ACME_ACCOUNT_KEY_FILE)) {
debug('getCertificate: generating acme account key on first run');
accountKeyPem = safe.child_process.execSync('openssl genrsa 4096');
if (!accountKeyPem) return callback(new AcmeError(AcmeError.INTERNAL_ERROR, safe.error));
safe.fs.writeFileSync(paths.ACME_ACCOUNT_KEY_FILE, accountKeyPem);
} else {
accountKeyPem = fs.readFileSync(paths.ACME_ACCOUNT_KEY_FILE);
}
acmeFlow(domain, email, accountKeyPem, outdir, callback);
}